N-(carbamyl) amide herbicides



United States PatentO 2,762,695 N-(CARBAMYL) AMIDE HERBICIDES Henry and Rayner S. Johnson,

New and Company, Delaware 'No Drawing. Application December 22, 1954,

Serial No. 477,102 '16 Claims. (Cl. 7'1-2.6)

J. Gerjovich, Wilmington,

Wilmington, DeL, a corporation of stituted phenyl radical, and at least one of the remaining valences is satisfied by a lower aliphatic hydrocarbon radical and any remaining valences is satisfied by hydrogen.

Castle, Del., assignors to E. I. du Pont de Nemours More specifically, the N-(carbamyl) amides 0f the invention are represented by the formula R,. L (H) M Where A and R are selected from the group consisting of I hydrogen, halogen, and alkyl of less than 5 carbon atoms, n is a positive integer less than 3 (i. e. 1 or 2), L, M, and Q are selected from the group of m-onovalent radicals consisting of hydrogen (-H), formyl I (iiand aliphatic hydrocarbon of less than 5 carbon atoms,

with the proviso that one and only one of L, M, and,

Q is formyl, and at least one but not more than two of L, M, and Q is an aliphatic hydrocarbon radical.

The preferred halogen substituent ischlorine. The preferred alkyl or aliphatic hydrocarbon radical substituent is methyl :or ethyl, most preferably methyl.

The N-(carbamyl) amides of the invention are suitably prepared, for example, by reaction of an amide with an isocyanate as shown in Equations 3 and 4 below, or with a carbamyl halide as shown in Equation 5 or by the reaction of a carbamyl halide, obtained according to Equation 6a, with a sodium salt .of an amide as shown in Equation 6b. While the equations below show the reaction of specific reagents to obtain specific compounds, it will be understood that these equations are for purposes of illustration only and that by suitable choice of the amide and the isocyanate or carbamyl halide reactant, the other N-(carbamyl) amides of the invention are similarly prepared.

to 20% molar excess of the amide.

2,762,695 Patented Sept. 11, 1956 The reactions illustrated above are preferably carried out in an inert solvent such as Xylene, toluene, or dioxane. The reaction is suitably carried out at a temperature in the range of about 15 to C. No catalyst excess, say 10 is needed but it is preferable to use an Processes of the kind illustrated by the foregoing equations are described in detail in examples given hereinafter of the preparation of illustrative specific compounds of the invention.

The -N-(carbamyl) amides of the invention are generally white crystalline solids. They are insoluble in water and moderately soluble in hydrocarbon solvents at room temperature. GeneraIIy they have sharp melting points with no indication of. decomposition.

Illustrative of the compounds of the invention represented by Formula 2 above are:

N- carbanilyl) -N-methylformamide N- (p-chlorocarbanilyl) -N-methylformamide N- 3 ,4-dichlorocarb anilyl) -N-methylform amide N- 2,4,5 -trichlorocarbanilyl) -N-methylformamide N- (m-chlorocarbanilyl) -N-methylformamide N- (p-bromocarbanilyl) -N-methylform amide N- o-chlorocarbanilyl) -N-methylformamide N- (p-methylc arb anilyl) -N-m ethylform amide N- m-methylcarbanilyl) -N-methylformamid e N- (p=isoprop ylcarbanilyl) -N-methylformamide N= (p-sec. butylcarbanilyl) -N-methylform amide N- (3 -chloro-4-me'thy1carb anilyl) -N-methylform amide N- (3 ,4-dichlorocarb anilyl) -N-ethylform amide N- (p-chlorocarbanilyl) -N-ethylformamide N- 3,4-dichlorocarb anilyl) -N-is opropylformarnide N- (p-chlorocarb anilyl) -N-is opropylformamide N-carb anilyl-N-isopropylform amide N- 3,4-dichlorocarb anilyl) -N-butylform amide N- dimethylcarb amyl -3,4-dichloroformanilide N- (methylcarbamyl) -3,4-dichloroformanilide N- (p-chloro-N-methylcarbanilyl) -N-methylformamide N-(ethylcarbamyDformanilide 'able herbicidal properties.

3 p-Chloro-N- (ethylc arb amyl formanilide N- (methylcarb amyl) formanilide p-Chloro-N- (dimethylcarb amyl) formanilide 3 -chloro-4-methyl-N- (methylcarbamyl) formanilide N- 4-chloro-3 -methylcarbanilyl) -N-methylformamide 3 -methyl-N- (methylcarb amyl) formanilide v N- 3 ,4-dimethy'lcarb anilyl -N-methylform'amide N- (dimethylcarb amyl) formanilide N- 3 ,5 -dimethylcarbanilyl) -N-methylfo rmamide N- (3 ,5 -dirnethylcarb anilyl) N-ethylforrnamide N- (carb anilyl) N-butylformamide N- (e'thylcarb amyl) 3 ,4-dichloroformanilide N- (p-chlorocarb anilyl) -N-allylformamide N- 3 ,4-dichlorocarb anilyl) -N-vinylform amide N- diallylcarb amyl) 3 ,4-dichloroformanilide N-(p-chlorocarb anilyl) N-(2-butenel-yl formamide N-(m-chlorocarbanilyl) -N-methallylformamide N- (dimethylcarb amyl) -p-chloroform anilide N- (diethylcarb amyl) -m-chloroformanilide N- N'-methylpropylcarb amyl) -formanilide N-(dimethylcarbainyl)-p-tert.butylformanilide N- (dimethylc arb amyl) -3 -chloro-4-methylformanilide N-( dimethylcarb amyl) -m-chloroform anilide N- (dimethylcarb amyl) -p-fluoroformanilide N- 3,4-dichlorocarbanilyl) -N- (Z-butyne-l-yl) formamide The N-(carbamyl) amides of the invention have valu- They can, for example, be used in application to crop lands to give substantially complete control of the common weeds without harming the crop plants. At higher dosages or rates of application, they can be applied to railroad right-of-ways, drainage ditches, power transmission line right-of-ways, and the like where complete kill of plant growth for extended periods-of time is desirable.

Herbicidal compositions of the invention are prepared by admixing -one-or more of the N-(carbamyl) amides defined heretofore, in herbicidally effective amounts, with a conditioning agent of the kind used and referred to in the art as a pest control adjuvant 'or modifier to provide formulations adapted for ready and eflicien't application to soil or Weeds (i. e., unwanted plants), using conventional applicator equipment.

Thus the herbicidal compositions or formulations are prepared in the form of solids or liquids. Solid compositions are preferably in the form of dusts and are compounded to give homogeneous freeflowingjdusts by admixing the active compound or compounds with "finely divided solids preferably tales, natural clays, pyrophyllite, diatomaceous earth or flours such as walnut shell, wheat, redwood, soya bean, cotton seed flours and other inert solid conditioning agents or carriers of the kind conventionally employed in preparing pest control compositions in dusts or powdered form.

Liquid compositions of the invention are prepared in the usual way by admixing one or more of the N-(oar' bamyl) amides with a suitable liquid diluent medium. With certain solvents such as alkylated naphthalene, dimethylformamide, and cresol, relatively high, up to about 35% by weight or more, concentrations of the N-(carbamyl) amide can be obtained in solution. Other liquids conventionally used in preparing liquid herbicidal compositions are for the most part less eifective solvents.

The herbicidal compositions of the invention whether in the form of dusts or liquids preferably also include a surface-active agent of the kind sometimes referred to'in the art as a wetting, dispersing, or emulsifying agent. These agents, which will be referred to hereinafter more simply as surface-active dispersing agents, cause the com-- positions to be easily dispersed in water to give aqueous sprays which, for them 0st part, constitute a desirable composition-for application.

The surface-active dispersing agents employed 'c an be of the anionic, cationic, or nonionic type and include,

for example, sodium and potassium -oleate, the amine salts of oleic acid such asimo'rpholine and dimethylamine oleates, the sulfonated animal and vegetable oils such as sulfonated fish and castor oils, sulfonated petroleum oils, sulfonated acyclic hydrocarbons, sodium salt of lignin sulfonic acid (goulac), alkylnaphthalene sodium sulfonate, sodium salts of sulfonated condensation products of naphthalene and formaldehyde, sodium lauryl sulfate, disodium monolauryl phosphate, sorbitol laurate, pentaerythritol monostearate, glycerol m-onostearate, diglycol oleate, polyethylene oxides, ethylene oxide condensation products with stearyl alcohol and octylphenol, polyvinyl alcohols, salts, such as the acetate of polyamines from reductive amination of ethylene/carbon monoxide polymers, laurylamine hydrochloride, laurylpyridinium bromide, stearyl-trimethylammonium bromide, cetyldimethylbenzyl ammonium chloride, lauryldimethylamine oxide, and the like. Generally, the surface-active agent will not comprise more than about 5 to 15% by weight of the composition, and in certain compositions the percentage will be 1% or less. Usually the minimum lower concentration will 'be 0.1%.

The herbicidal compositions are applied either as a spray or a dust to the locus or area 'to be protected from undesirable plant growth, commonly called weeds, i. e., plants growing where they are not wanted. Such application can be made directly upon the locus or area and the weeds thereon during the period of Weed infestation in order t'o'destroy the weeds, but preferably, the application 'is made in advance of an anticipated Weed infestation to prevent such infestation. Thus, the compositions can be applied as aqueous foliar sprays but can also be applied as sprays directly to the surface of the soil. Alternatively, the dry powdered compositions can be dusted directly on the plants 'or on the soil.

In applying the herbicidal compositions of the invention for selective weed control as in the control of weeds in cotton or corn fields, the compositions are preferably applied after planting of the crop seeds but before emergence of the seedlings. In other words, the applications are of the pre-emergence type.

The active compound is, of course, applied in amount su'flicient to exert the desired herbicidal action. The amount of the active compound present in the compositions as actually applied for destroying or preventing we'eds will vary with the manner of application, the particular weeds for which control is sought, the purpose for which the application is being made, and like variables. In general, the herbicidal compositions as applied in the form of a spray or a dust will contain from about 0.5% to of N-(carbamyl) amide.

vention if desired.

In order that the invention may be better understood, the following examples are given in addition to the examples already given above. The examples illustrate a -method for making the compound of the invention,

herbicidal formulations employing the compound, herbicidal applications, and the results obtained. The numbers following tabulated ingredients in the examples represent parts by weight of the ingredients in the compositions.

EXAMPLE 1 ture for one hour. The hot solution was then treated with decolorizing carbon, filtered, and the filtrate allowed to cool. There was obtained by crystallization from the filtrate a total of 52.9 parts by weightof white crystalline -(3,4-dichlorocarbanilyl)-N-methylformamide, M. P. 141-2 C.

Analysis.-Calcd. for CsHsClzOz: 11.33. Found: Cl, 28.4; N, 10.70.

EXAMPLE 2 6 parts by Weight of N-methyl formamide, 15.5 parts by weight of p-chlorophenyl isocyanate and 150 parts by weight of toluene were mixed and heated at reflux temperature for 4 hours under anhydrous conditions. The toluene was removed under reduced pressure and the residue recrystallized from hexane. There was obtained in yield corresponding to 77% of the theoretical amount white crystalline N-(p-chlorocarbanilyl)-N-methylformamide, M. P. 98-100 C.

Analysis.Ca1cd. for CsHsClNzOz; C1, 16.70; N, 13.17. Found: C], 16.51; N, 13.09.

EXAMPLE 3 39.9 parts by weight of 3,4-dichloroformanilide, 10.4 parts by weight of methyl isocyanate and 150 parts by weight of benzene were mixed and heated to reflux temperature for 4 hours under anhydrous conditions. The benzene was removed under reduced pressure and the residue recrystallized from ethanol. There was obtained white crystalline N-(methylcarbamyl)-3,4-dichloroformanilide, M. P. 120-121 C.

Analysis.-Calcd. for C9H9Cl2N2O2: Cl, 28.70; N, 11.33. Found: Cl, 29.04; N, 11.53.

Additional examples of the herbicidally active compounds of the invention prepared according to the methods described heretofore are:

EXAMPLE4 N (3,5 dimethylcarbanilyl) N methylformamide. M. P. 103-105 C.

Calcd. for CuHmNzOz: N, 13.6. Found: N, 13.8. The compound was prepared by the reaction of 3,5- dimethyl isocyanate with N-methylformamide.

EXAMPLE 5 N-(3,5-dimethylcarbanilyl)-N-ethylformamide, an oil.

Calcd. for C12H16N2O2: N, 13.7. Found: N, 13.4.

The compound was prepared by the reaction of 3,5- dimethyl phenyl isocyanate with N-ethylformamide- EXAMPLE 6 N (p chlorocarbanilyl) N-ethylformamide. M. P. 103-104" C.

Calcd. for C1oH11ClN2O2: Found: N, 12.34; Cl, 15.68.

This compound was prepared by the reaction of parachlorophenyl isocyanate with N-ethylformamide.

EXAMPLE 7 N- (p-chlorocarb anilyl) -N-ally1formamide. 63 C.

Calcd. for C11H11C1N2O2: Found: N, 11.65; Cl, 14.73.

The compound was prepared by the reaction of parachlorophenyl isocyanate with N-allyformamide.

EXAMPLE 8 N (carbanilyl) butylformamide. M. P. 65- 66.5 C.

Calcd. for C12H1eN2O2: N, 11.0; C1, 13.95. Found: N, 11.07; Cl, 13.97.

This compound was prepared by the reaction of phenyl isocyanate with N-butylformamide.

EXAMPLE 9 N-(3,4-dichlorocarbanilyl)-N-ethylformamide. M. P.

Cl, 28.70; N,

N, 12.36; Cl, 15.67.

N, 11.74; Cl,

6 Calcd. :for CioHmClzNzOz: N, 10.73; Cl, 27.20. Found: N, 10.76; Cl, 26.99.

This compound was prepared by the reaction of 3,4- dichlorophenyl isocyanate with N-ethylformamide.

EXAMPLE 1O N-(carbanilyl)-N-methy1formamide. M. P. 54-55 C.

Calcd. for C9H10N2O2: N, 15.73. Found: N, 15.77.

This compound was prepared by the reaction of phenyl isocyanate with N-methylformamide.

:EXAMPLE 11 N- o-chlorocarbanilyl) -N-methylformamide. 79.5-80.5" C.

Calcd. for C9H9C1N2Oz: N, 13.15; Cl, 16.65. Found: N, 13.31; Cl, 16.25."

This compound was prepared by the reaction of ochlorophenyl isocyanate with N-methylformamide.

. EXAMPLE 12 N-(m chlorocarbanilyl) -N-methy1formamide. M. P. 96-97 C.

Calcd. for C9H9C1N2O2: N, 13.7; C1, 16.7. Found: N, 13.56; C1, 1663. v

This compound was prepared by the reaction of mchlorophenyl isocyanate with N-methylformamide.

EXAMPLE 13 N(m-methylcarbanilyl)-N-methylformamide. M. P. 69-70 C.

Calcd. for C10H12N2O2: N, 14.58. Found: N,'14.58.

This compoundwas prepared by the reaction of mmethylphenyl isocyanate with N-methylformamide.

EXAMPLE 14 N 3-chloro-4-methylcarbanilide) -N-methylformamide.

P. 99.5-101.5 C. "Calcd. for C10H11C1N2O2: N, 12.37; Cl, Found: N, 12.28; CI, 15.9.

This compound was prepared by the reaction of 3- chloro-4-methylphenyl isocyanate with N-methylformamide. I

- EXAMPLE 15 N-(methylcarbamyl)formanilide. M.'P. 143 C. (d). Calcd. for C9H10N202: N, 15.73. Found: N, 1578. This product was prepared by the reaction of methyl isocyanate with formanilide;

EXAMPLE 16 N-(ethylcarbamyl)formanilide. M. P. 120.5-122.5 Calcd. for C1oH12N2O2: N, 14.58. Found: N, 14.96. This compound was obtained by the reaction of ethyl isocyanate with formanilide.

I EXAMPLE 17 Found: N, 10.12; Cl, 27.27.

. This compound was obtained by the reaction of 3,4-

dichloroformanilide, sodium' salt; with dimethylcarbamyl chloride.

EXAMPLE 2.0.

Water-dispersible powders The, following powdered compositions,- are adapted for dispersing intwater for. application as axspray. for the destruction and prevention of weeds. The powdered compositions are'made by intimately mixing the listedim gredients using conventional mixing or blending equipment and then grinding the mixture to give a powder having an averageparticle sizewless than :aboutSO microns.

N-(3,4 dichlorocarbanilyl) N methylformaniide Fullers. earth 23;75

Sodium lauryl sulfate, 50% (wetting agent) 1 The following compositions are adapted for direcbapplication as dusts for'the destruction or prevention of weedsusinggconventional dustingequiprnent. The. dusts aremadeby blending or mixing; the. ingredients and grindingthe, mix --to give compositions-having an average particle size less than about 50.microns..

Nrcarb'anilyl-N methy1f01'mamide "a"..- 2O Talc 80 N-(3,4 dichlorocarbanilyl) -N=rnethylacetamide 5 Gottonseed .o 4 Walnut shell flour 9-1 EXAMPLE 22.

Oil-water'dispersible powders The following powdered compositions are adapted for use in -thepreparation of spray compositions using either an oil, water, or 'a combination of oil and'ewaten as --the liquid diluent: The'powdersaremade by-mixingand grinding as inthe case of flhe-powders of ExampleZ'l.

-N-( 3,4 dichlorocarbanilyl) -N-methylformamide.. 70 Alkyl-ated aryl polyethe-r alcohol (wetting and dispersing agent) 4 Fullers earth; 26

Nj-(p-chlorocarbanilyl)-Nethylformamid 8O Ethylene oxidestearate-laurate (emulsifying agentu 4 Pyrophylliter 16 v a 100 EXAMPLE 23 Water-dispersible liquid compositions Thefollowing compositions'are in. a liquid form and are adapted forv addition-to water to. give. aqueous dispersions for. application as, sprays. The N-(carbamyl) amides-aregenerally quite insoluble in most oils. Therefore,concentrated-liquid.compositions ordinarily are not complete. solutions but rather are in part dispersions of sOlid'in an 1 oil. The liquid or fluid compositions-shown are preparedbythoroughly mixing and dispersingthe active compounds and conditioning agent or agents in an organic liquid, diluent; The formulations shown below are solutions because the N-(carbamyl) amidesemployed are among the most soluble members of the class.

N.#(methy-lcarbamyl)-3,4-dichloroformanilide 25 Long; chain; fatty: alcohol sulfate (emulsifying agent).

Goulac. (dispersing, agent) 3 Kerosene 70 N- dimethylcarb amyl) .p-chloroformanilide 3 0 Alkylated aryl-polyetheri alcohol (wetting and emulsifying agent) 3 Methyl cellulose (dispersing agent) 1 Kerosene 66 EXAMPLE. 24

Granular compositions The following compositions are adapted for application by means. of; a. fertilizer spreader apparatus or similar equipment. The compositions are readily. prepared. by mixing the ingredients with water to form a paste. The paste is then extruded,tdried, and ground to give the desired granular size. Preferably, the granules will be in the order of one-thirty second to onequarter inch diameter;

N 3;4-dichlorocarbanilyl) -N-methylformamide 10 Goulac (dispersing. agent) 3 Hydrocarbon oil 1 Dextrin (binding agent) 20 Fullers earth 66 N (3 chloro 4- -methyilcarb'an ilyl)N-methylformamide Goulac 3 Refined kerosene 1 Gelatin 25 Talc 64 EXAMPLE 25 A water-dispersible powder containing by weight of N-(p-chlorocarbanilyl)rN-methylformamide was dispersed in water and applied as an aqueous spray to an area newly planted" withcottonandcorn seed, and heavily infested with weed seeds, both broad leaf and" grasses.

Different dosages or rates of application were made on dififerent areas.

Four weeks later, it was found that the aqueous preemergence treatments gave 88% control of weeds at a dosage of one pound of the N-(carbamyDamide per acre, 98% control at a dosage of three pound per acre, and 100% control at six pounds per acre whereas an untreated check area had many weeds. Neither the corn or cotton plants were in any way injured by these treatments.

There follows a tabular form the results obtained with an illustrative number of compositions of the invention in pre-emergence treatments of the kind disclosed in Example 25. As in Example 25, the N-(carbamyl) amides were applied in a form of an aqueous dispersion of a water dispersible powder containing 80% by weight of the N-(carbamyl) amide to areas newly planted with cotton and corn seed and heavily infested with Weed seeds of both the broad leaf and grass kinds. Observations and measurements were made four weeks after treatment, comparison being made with untreated check areas. The tabulated results show the amount of the N-(carbamyl) amide used to obtain at least 90% control of the weeds. In no case, were the corn or cotton plants injured by the treatments.

Dosage Ex- 111 lbs. ample N-(carbamyl) amide acre to N umgive 90% bar weed control 26 N (p-chlorocarbanilyl) -N -a11ylforman1ide 4. 27 N -(carbanilyl) -N -butylf0rman1ide 3. 0-4. 0 28 N (o-chlorocarbanilyl) -N-rnethylformamlde 3. 0 29 N-(rn-chlorocarbanllyl)-N-methylformamide 0. 30 N (3,4-clichlorocarbanilyl) -N -methylformamide 1. 0 31 N -(m-methylcarbanilyl) -N -methylforrnamlde 1. 0 32 N-(methylcarbamyl) iormanilide 0.5-1.0 33 N (ethylcarbamyl) formanilide 1. O 34 N (methylcarbamyl)-3,4-dichloroforma 0. 5-1. 0 35 N-(ethylcarbamyl)-3,4-dichloroformanilide 4. 0 36 N (dimethylcarbamyl) formanilide 0. 5-1. 0 37 N (dimethylcarbamyl) -3, d-dichloroformanilide. 0. 5-1. 0

This application is a continuation-m-part of our copending application Serial No. 385,895, filed October 13, 1953, and now abandoned.

Those skilled in the art will appreciate that other N- (carbamyl) amides and other herbicidal compositions of the invention can be prepared and applied in accordance with the foregoing examples. Thus the foregoing detailed description has been given for clearness of understanding only and no unnecessary limitations are to be understood therefrom.

We claim:

1. An N-(carbamyl) amide represented by the formula t t t 33 t N A where A and R are selected from the group consisting of hydrogen, halogen, and alkyl of less than 5 carbon atoms, n is a positive integer less than 3, L, M, and Q are selected from the group of monovalent radicals consisting of hydrogen, formyl, and aliphatic hydrocarbon 10 of less than 5 carbon atoms, with the proviso that one and only one of L, M, and Q is formyl, and at least one but not more than two of L, M, and Q is an aliphatic hydrocarbon radical.

2. A herbicidal composition comprising a conditioning agent and in amount sufficient to exert herbicidal action, an N-(carbamyl) amide of claim 1.

3. A method for the prevention or destruction of Weeds which comprises applying to a locus to be protected in amount sufiicient to exert a herbicidal action, an N-(carbamyl) amide represented by the formula Rn LOM where A and R are selected from the group consisting of hydrogen, halogen, and alkyl of less than 5 carbon atoms, 11 is a positive integer less than 3, L, M, and Q are selected from the group of monovalent radicals consisting of hydrogen, formyl, and aliphatic hydrocarbon of less than 5 carbon atoms, with the proviso that one and only one of L, M, and Q is formyl, and at least one but not more than two of L, M, and Q is an aliphatic hydrocarbon radical.

4. A herbicidal composition comprising a surface-active dispersing agent and, in amount suflicient to exert herbicidal action, an N-(carbamyl)amide of claim 1.

5. N-dimethylcarbamyl)-3,4-dichloroformanilide.

6. N-(dimethylcarbamyl)-p-chloroformanilide.

7. N- (m-chlorocarbanilyl)-N-methylformamide.

8. N- (p-chlorocarbanilyl) -N-methylformamide.

9. A herbicidal composition comprising a conditioning agent and, in amount sufiicient to exert herbicidal action, N- (dimethylcarbamyl) -3,4-dichloroformanilide.

10. A herbicidal composition comprising a conditioning agent and, in amount sufiicient to exert herbicidal action, N-(dimethylcarbamyl)-p-chloroformanilide.

11. A herbicidal composition comprising a conditioning agent and, in amount sufiicient to exert herbicidal action, N- (m-chlorocarbanilyl) -N-methylformamide.

12. A herbicidal composition comprising a conditioning agent and, in amount sufiicient to exert herbicidal action, N- (p-chlorocarbanilyl) -N-methylformamide.

13. A method for the prevention or destruction of weeds which comprises applying to a locus to be protected, in amount sufiicient to exert a herbicidal action,

- dimethyl-carb amyl) -3,4-dichloroformanilide.

14. A, method for the prevention or destruction of weeds which comprises applying to a locus to be protected, in amount sufiicient to exert a herbicidal action, N-(dimethylcarbamyl)-p-chloroformanilide.

15. A method for the prevention or destruction of Weeds which comprises applying to a locus to be protected, in amount sufiicient to exert a herbicidal action, N- (m-chlorocarb anilyl) -N-methylformamide.

16. A method for the prevention or destruction of weeds which comprises applying to a locus to be protected, in amount sufiicient to exert a herbicidal action, N- (p-chlorocarbanilyl) -N-methylformamide.

References Cited in the file of this patent 

1. AN N-(CARBAMYL) AMIDE REPRESENTED BY THE FORMULA 